1. Field of the Invention
The invention relates to a mechanical transmission with which a fixed or variable transmission ratio can be realized between two rotating parts.
2. Description of the Related Art
The European patent no. 0 688 407 describes a mechanical transmission which comprises a frame, a first shaft arranged rotatably in the frame and a second shaft arranged rotatably in the frame, which second shaft is parallel to and eccentric relative to the first shaft. The first shaft carries a pair of conical friction wheels, between which a push belt is placed. The second shaft comprises an engaging wheel which reaches between the friction wheels and engages with the push belt. By displacing the second shaft in a direction at a right angle to the axial direction the push belt will displace between the friction wheels, whereby a different transmission ratio is realized.
A drawback of the above described transmission is that the second shaft has to be displaceable. This requires major structural measures in order to make the shaft displaceable and also to enable driving of anything with the shaft.
Another drawback is that the range of transmission ratios which can be adjusted is limited.
It is an object of the invention to obviate the above stated drawbacks. It is a further object of the invention to provide a transmission with a limited number of components.